What a Heated Basketball Game Can Do to a Coach's Body

As head coach of the Michigan State men's basketball team, Tom Izzo's job is as high stress as they come. One of the highest-paid college coaches in the country, his teams are expected, year in and year out, to be national championship contenders.

Izzo, a dedicated family man with a wife and two kids, is known as one of the nicest guys in college sports, but come game day he's also known as one of the most animated coaches in NCAA basketball.

Outwardly, Izzo displays plenty of passion during a game but what's going on inside his body while he does all that yelling, jumping and hand wringing?

To find out what can happen to a coach's health during the heat of battle, Izzo gave "Nightline," in conjunction with ESPN's Sport Science, unprecedented access to his body, agreeing to be rigged up with a bio-harness and accelerometer. He also had to swallow an ingestible thermometer, a special sensor that tracked core body temperature. These devices measured heart rate, respiratory rate, core body temperature, skin temperature, calories burned and the number of steps taken.

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ESPN Sport Science's John Brenkus (left) talks with Michigan State's Tom Izzo (right) as the coach gets wired up for the health experiment.

Izzo was monitored during Michigan State's March 1 home game against Illinois, which the Spartans lost 53-46. Despite the loss, Izzo showed he is in good shape for a 59-year-old man to handle the pressures of the game.

Coaches are no stranger to health issues. Two NFL head coaches has to sit out last season due to health problems, including former Houston Texans coach Gary Kubiak, who suddenly collapsed on the sideline as his team was leaving the field for halftime during a November game against the Colts.

Earlier this month, Duke University men's basketball Coach Mike Krzyzewski went to the hospital after feeling light headed during a game against Wake Forest, but was back at practice the following day. Just over a year ago, acclaimed basketball coach Rick Majerus died of heart failure at age 64.

While Izzo said he has never had any major health issues, doctors say his high-stress job could make him more susceptible to health problems.

His vital signs were monitored courtside throughout the game from a laptop, with Duke University Medical Center stress expert Dr. Redford Williams analyzing the live results.

Before the game, Izzo had a resting respiratory rate of about 14 breaths per minute and a heart rate of 68 beats per minute. As the game was getting ready to start, Izzo's breating rate rose to 36 breaths per minute and his heart rate went up to 97 beats per minute. Then when Illinois scored the first basket of the game, Izzo's heart rate immediately spiked to 120.

The data from the sensors indicated that Izzo's heart rate was connected to his emotional response to the game. As Illinois kept scoring and racking up point on his team, Izzo's body continued to react.

Just nine minutes into the game, Michigan State was down by 12 points. Izzo's heart rate stayed at 120 beats per minute and his core body temperature approached 100 degrees. By halftime, the Spartans had made a comeback and the game was tied.

At their peak, Izzo's vitals showed his heart rate had spiked to 135 beats per minute and his body temperature was at 100 degrees. But as it became clear in the second half that the Illinois lead was too much for Michigan State , the sensors showed Izzo's heart rate and body temperature start to drop, almost as if his body was conceding defeat. With 1:06 left and the game out of reach, Izzo's heart rate had dropped back down in the 90s.

When Izzo reviewed the results, which showed that even if he was sitting on the sideline his heart was working at 70 percent of its max, he was surprised by how his body reacted.

"Especially coming from a guy who has run a couple of marathons, that really does surprise me," he said.

"I don't try to hide my emotion very often. Sometimes it gets me in trouble, sometimes not... These are emotional games and I guess the good news for me is stay pretty true to form," Izzo continued. "I do think… most coaches have… gotten this far because they can handle things because there are stressful things that happen each and every day in these jobs."